石膏, 又称水合硫酸钙, is a naturally occurring mineral found in layers of sedimentary rock all over the world. It is formed by the evaporation and replenishment of 水s containing calcium and sulfates.
白色或灰色的, gypsum can be ground into a fine powder and boiled until the majority of its moisture is removed — a process known as calcination. Adding the 水 back to this powder creates a pliable substance that can be formed into a shape or mold and will harden to hold that form, or the substance can be added to other materials to bind them together.
Because of its binding abilities, gypsum is a primary ingredient in some toothpastes. It is also used as plaster to create surgical casts; as an additive in many foods, 比如蔬菜罐头, ice cream and tofu; and as an 改良剂、调理剂和肥料 农业应用.
石膏的其他用途包括:
- 用于在池塘中沉淀颗粒
- 用来酿造啤酒和制作蜂蜜酒
- For creating drywall, wallboard or plasterboard
- 用于捆绑网球场粘土
- As molds for dinnerware, car windows and dental impression plasters
- 作为波特兰水泥中的硬化元素
- 在道路和高速公路
- 如人行道粉笔或教室粉笔
- 在护发菠菜网最稳定正规平台_最全菠菜网大全中，比如洗发水和面霜
- 还有很多很多.
Although gypsum plays an important role in our lives and is found in many of our homes, 食品及卫生用品, many people do not know much about this mineral or even that it exists at all. Here are some lesser-known facts about this mineral that is a mystery to many.
1. 它是许多早期电影的明星
在计算机生成图像时代之前, early Hollywood filmmakers used a number of substances to 在布景上制作假雪, including cotton, cornflakes and soap flakes. 的y also used shaved gypsum to mimic the look of real snow.
But snow isn’t the only role gypsum has played on the silver screen. One of its recurring roles is in the creation of movie sets.
Since gypsum is common in the production of sidewalks, it stands to reason that the mineral may have been cemented in the Hollywood Walk of Fame. 星星是由 水磨石, which is composed of marble chips, granite, quartz or glass and poured on a concrete base. 混凝土 is often bonded with Portland cement so that it can harden, 石膏是波特兰水泥的一种成分.
2. 它在埃及金字塔中被发现
When the Egyptians learned that gypsum could be made into plaster by grinding it up and adding 水, 他们在家里到处用 宫殿、金字塔和坟墓. As it still holding up thousands of years later, gypsum proves to be a durable building material.
3. 它是由古希腊人命名的
的 name “gypsum” is derived from the ancient Greek word “gypsos,” which means plaster. 的 古希腊人 used a form of gypsum in the windows of their temples because of the moonlight effect it created on the altars when the sun shone through. 的 古希腊人 named this form of gypsum “selenite” after their moon goddess, 月之女神, 这个名字沿用了这么多年.
4. 本·富兰克林在他的农场里使用石膏
本杰明·富兰克林是 第一批人之一 在美国使用石膏. He called it “land plaster” and put it to work on his farm to condition the soil. This land plaster is still used in agricultural applications today to provide a source of plant nutrition, to improve the structure of the soil and to reduce runoff, 其他好处包括.
5. 石膏涂层的墙壁具有防火功能
的 walls and ceilings of many houses are covered with drywall because it is both easy to install and simple to finish with a coat of paint. 但干, 哪个是石膏做的, offers another benefit to homeowners besides ease of decorating – it offers 发生火灾时的保护措施.
Because gypsum contains 水, it will not heat past 212° F should a fire occur in the home. 的 水 in the gypsum will be released as steam and the drywall will remain at 212° F until all the 水 has evaporated out. 虽然石膏不防火, it will protect the structure of the house from damage for a period of time.
石膏是如何加工的?
石膏 in its natural state is an ore often found layered with limestone. It is liberated from its natural state most commonly by surface mining. To get the gypsum ore into a state where it can be sold for its many uses, 它被粉碎成大小使用 DDC-Sizers, Feeder-Breakers, 锤磨机破碎机, 颚破碎机 or 辊破碎机 并储存起来等待进一步处理.
一台菠菜网最稳定正规平台_最全菠菜网大全 ddc - size机.
粉碎后的石膏用筛网筛分 振动屏幕 to separate the sizes for their different uses. One size from the screen may be sold as a cement retarder, while another size may be stockpiled for further processing. Further processing includes drying the ore to remove excess moisture, then grinding it into a fine powder known as land plaster. 地面灰泥收集在一个 Hydrocylcone, discharged onto a conveyor and stockpiled for sale as a soil conditioner.
制造灰泥, the land plaster is heated with hot gasses either directly in a flash calciner or indirectly in a kettle calciner to remove much of the chemically bound 水. 的 stucco can be further ground and mixed with retarders to create plasters, 也可与干燥添加剂混合使用, 水, 粉碎后的纸, accelerators and soap foam; spread in a mold; and dried in a kiln to create wallboard.
石膏就在我们身边
下次你坐在家里的时候, 打网球, 刷牙, washing your hair or even just walking down the sidewalk, think about how all these items are possible because of a little known mineral called gypsum.
